Tall-sedge base-rich fen
Quick facts
| Red List habitat type | code RLD4.1b |
|---|---|
| Threat status | |
| Europe | Endangered |
| EU | Endangered |
| Relation to |
|
| Source | European Red List habitat factsheet |
| European Red List of habitats reports | |
| European Red List of habitats (Excel table) |
Summary
Tall-sedge base-rich fens are dominated by the tall to medium-tall graminoids Cladium mariscus, Juncus subnodulosus, Schoenus ferrugineus (in subcontinental areas) and S. nigricans (in Atlantic and Mediterranean areas). In some stands also Phragmites australis occurs, but it does not form dense stands. Small sedges and short-growing herbs also occur in places, but their number and abundance are smaller here than in small-sedge fens. Stands with Cladium mariscus can be very dense and species-poor.
These fens typically occur on flat landforms in lowlands and submontane areas near springs with base-rich water, especially where the bedrock is formed of limestone, chalk or marl. They are generally wetter than the other types of base-rich fens and their water table is high also in summer. In places, long-term inundation of the soil surface can result in the occurrence of muddy patches with sparse vegetation after draw-down, which are microhabitats of Drosera anglica and the moss Scorpidium scorpioides.
Tall-sedge base-rich fens occur across the entire European continent, but they are considerably more common in the Atlantic and boreal regions and in the lowland areas of Central Europe, where they are the main type of base-rich fens.
Based on the palaeoecological evidence, tall-sedge base-rich fens were more common in the Late Pleistocene and early Holocene than today in non-glaciated parts of Europe, but they changed into Sphagnum fens after landscape acidification or retreated as a result of terrestrialisation of wetlands in the course of natural succession. In the last two centuries many of these fens have been destroyed due to artificial drainage. Some of these fens are grazed or occasionally cut, but at many sites their vegetation is natural and does not depend on management.
Indicators of good quality:
- Stable hydrological regime
- Absence of overgrazing
- No encroachment of trees or shrubs
- No spread of meadow or reed species
Threat status
Synthesis of Red List assessment
| EU | |
| Red List Category | Red List Criteria |
| Endangered | A1 |
| Europe | |
| Red List Category | Red List Criteria |
| Endangered | A1 |
Confidence in the assessment
Pressures and threats
- Agriculture
- Modification of cultivation practices
- Agricultural intensification
- Grassland removal for arable land
- Mowing / Cutting of grassland
- Abandonment / Lack of  mowing
- Grazing
- Intensive grazing
- Intensive cattle grazing
- Abandonment of pastoral systems, lack of grazing
- Pollution
- Pollution to surface waters (limnic, terrestrial, marine & brackish)
- Diffuse pollution to surface waters due to agricultural and forestry activities
- Diffuse pollution to surface waters due to transport and infrastructure without connection to canalization/sweepers
- Soil pollution and solid waste (excluding discharges)
- Other forms of pollution
- Natural System modifications
- Human induced changes in hydraulic conditions
- Landfill, land reclamation and drying out, general
- Reclamation of land from sea, estuary or marsh
- Canalisation & water deviation
- Modification of hydrographic functioning, general
- Water abstractions from groundwater
- Management of aquatic and bank vegetation for drainage purpose
- Other ecosystem modifications
- Anthropogenic reduction of habitat connectivity
- Natural biotic and abiotic processes (without catastrophes)
- Biocenotic evolution, succession
- Species composition change (succession)
- Climate change
- Changes in abiotic conditions
- Droughts and less precipitations
Habitat restoration potential
Through intervention restoration is extremely difficult as demonstrated by several studies, especially because of problems with nutrient oversupply and iron toxicity.
Trends in extent |
|
Average current trend in quantity |
|
Decreasing  |
Decreasing |
| EU28 | EU28+ |
Trends in quality |
|
Average current trend in quality |
|
| Decreasing |
Decreasing |
| EU28 | EU28+ |
Conservation and management needs
No intervention - in well waterlogged, nutrient-poor fens, especially in high-boreal and some mountain regions.
Mowing - in fens enriched in nutrients or with a lowered water level, in fens invaded by Phragmites, Calamagrostis, Filipendula or tall sedges and willows.
Artificial disturbances - if acidicole, late-successional Sphagnum species invade, disturbances without nutrient input (e.g., removal of expanding peatmosses) may be applied to support original brown-moss vegetation.
Creating buffer zones filtering nutrients and hydrological buffer zones.
Extensive restoration measures (blocking drainage channels, sod removal, planting Pedicularis palustris as a hemiparasite to supress reed and tall sedges) in heavily damaged fens.
List of conservation and management needs
- No measures
- No measures needed for the conservation of the habitat/species
- Measures related to agriculture and open habitats
- Maintaining grasslands and other open habitats
- Measures related to wetland, freshwater and coastal habitats
- Restoring/Improving water quality
- Restoring/Improving the hydrological regime
- Managing water abstraction
- Measures related to spatial planning
- Establish protected areas/sites
- Legal protection of habitats and species
- Manage landscape features
- Measures related to urban areas, industry, energy and transport
- Urban and industrial waste management
Distribution
Geographic occurrence and trends
| EU28 | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
|---|---|---|---|---|
| Austria | Present | 3.9 | Decreasing | Decreasing |
| Belgium | Present | 0.1 | - | - |
| Bulgaria | Present | 0.01 | Decreasing | Decreasing |
| Croatia | Present | Unknown | - | - |
| Czech Republic | Present | 0.6 | Decreasing | Decreasing |
| Denmark | Present | Unknown | - | - |
| Estonia | Present | 55 | - | Unknown |
| Finland mainland | Present | 0.05 | Unknown | Decreasing |
| France mainland | Present | 125 | Decreasing | Decreasing |
| Germany | Present | 10 | Decreasing | Decreasing |
| Crete | Present | 0.1 | - | - |
| Hungary | Present | 8.5 | Decreasing | Unknown |
| Ireland | Present | 90 | Decreasing | Decreasing |
| Italy mainland | Present | 13 | Decreasing | Decreasing |
| Latvia | Present | 2.2 | Decreasing | Decreasing |
| Lithuania | Present | 1 | Decreasing | Decreasing |
| Netherlands | Present | - | Decreasing | |
| Poland | Present | 45 | Decreasing | Decreasing |
| Romania | Present | 10 | Decreasing | Decreasing |
| Slovakia | Present | 10 | Decreasing | Decreasing |
| Slovenia | Present | 1 | Decreasing | Decreasing |
| Spain mainland | Present | 33 | Decreasing | Decreasing |
| United Kingdom | Present | 4.2 | Decreasing | Decreasing |
| Sweden | Present | 75 | Unknown | Decreasing |
| EU28 + | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
|---|---|---|---|---|
| Albania | Present | 3 | Decreasing | Decreasing |
| Bosnia and Herzegovina | Present | 15 | Decreasing | Decreasing |
| Former Yugoslavian Republic of Macedonia (FYROM) | Present | Unknown | Unknown | Decreasing |
| Switzerland | Present | 30 | Decreasing | Decreasing |
| Norway Mainland | Present | 10 | - | Decreasing |
Extent of Occurrence, Area of Occupancy and habitat area
| Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
|---|---|---|---|---|
| EU28 | 7465150 | 2054 | 488 | |
| EU28+ | 2254 | 536 |
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).
